This is correct of course. However, it ignores the point as this greatly inconveniences normal, legitimate customers.
Normal customers usually return defective items, or if it is an article of clothing, they may exchange it for a different size, or maybe even have a case of buyer's remorse every now and then. These kinds of customers are not the "serial returners" to which this article refers.
Most stores have no problem accommodating good customers which make sensible use of return policies. However, all retailers should guard against people who abuse these policies.